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1999 forester s turbo
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Discussion Starter #1
TD04 or TD05-That is the question: There aint much difference in the price of second hand ones. So which is it be on a UK 99 s turbo auto?
 
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For an auto you need to keep it as small as possible to avoid gear change problems, I would say TD04 myself, you can get 270 bhp from one..
 

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2015 Triumph Tiger XCx 1 Down. 5 Up.
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I agree, VF35 if you can find one for decent money... I'm going for a TD04 though as it was only £50 and should give 270 - 280bhp with supporting mods and will spool faster than a TD05 so the power should be more usable.
 

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2015 Triumph Tiger XCx 1 Down. 5 Up.
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It's a TF035 on the 2.0 XTs which is tiny and can just about make 230bhp... straight swap for a TD04 though, which is nice ;o)

Getting mine fitted at the end of July along with a decat centre pipe... just before a trip to see Bob Rawle to map it again ;o)
 

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05 XT2.5
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I've had a TD04 and a TD05 and the 5 spools faster. It ain't just the numbers it's whether it's a decent turbo or a POS.

Not only does the 5 spool faster it makes a heap more power.

In my current tune we've slowed down the spool so that it is actually possible to drive it off boost. It's a much nicer and more economical drive.

In fact now I think about it my 5 is the Blouch that is actually a TD06.
 

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99 UK S-turbo
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No way a TD05 or 6 will spool faster on an EU 2.0 than a TD04, launches with too large a turbo will be a PITA, you'll just about get on boost on a launch with a TD04, so would suggest that route myself, 260bhp is easy with a TD04, 280 a stretch (you drop about 20bhp to Impreza numbers due to the softer cams).

Simon
 

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2005 2.0XT Auto
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What TD04 would I need for my XT? Is it a WRX one and if so, what year, type?

Step forward Gigsy... :N_poke:
 

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99 UK S-turbo
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All stnd Subaru TD04's are the same, those fitted to 2.5's have a larger wastegate apeture, but that won't make any difference on a 2.0.

So yes any newage WRX or classic turbo (UK or WRX wagon/JDM foz) TD04 (front entry so 97MY on) will be fine.

Simon
 

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98 JDM Stb Manual
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3,787 Posts
Just looking in my pile of bits.......................................



Hello..........................................................................





Is this a turbo?





Yes












mmm TDO4 with 45000 miles on it





£50 + postage
 

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05 XT2.5
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No way a TD05 or 6 will spool faster on an EU 2.0 than a TD04, launches with too large a turbo will be a PITA, you'll just about get on boost on a launch with a TD04, so would suggest that route myself, 260bhp is easy with a TD04, 280 a stretch (you drop about 20bhp to Impreza numbers due to the softer cams).

Simon
Interestingly that's not what mr Dyno said. My car is a 2.5 though. Everyone talks about spool but it's a complex subject until you've had a few different turbos on the same car. The stock turbo is on boost quickly but even when it is it's a bit yawn..... The TD04 with the 'big' housing is just as quick onto boost but there's much more - to the point where it's quite hard to drive smoothly. You want a reasonable amount of acceleration but you move your foot a milimeter too far and your head is bashed into the headrest. Fun for a while but eventually annoying and possibly dangerous to transmission/engine longevity. The power drops off way before the redline. The TD05(6) is no slower onto boost but doesn't produce an annoying spike - the power builds in a smoother way. The effect in a drag race would be that the 4 car might snatch a car length in the first second but after that would be a dot in the mirrors of the 5 car. The stock turbo car would look like it's in reverse.....

So I wouldn't advocate a road car that makes no power until 4500rpm but spool is what happens in the first second of acceleration. What happens in the next 10 should also be considered.
 

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99 UK S-turbo
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Strictly spool is not related to rpm, but gasflow and inertia, a TD04 has a lot less inertia that a TD05 or 06 so will spool faster for the same exhaust gas flow (ignoring any wacky A/R's!)....of course if you modify the target boost to make it more driveable it will feel like the spool is slower.

Many say you can't feel any lag on a TD04, as I can feel lag on a TF035 I think that is more a case of an individuals perception than what is actually happening!

Of course lag/spool and personal prefernace for how they want something to 'feel' is a major factor and very subjective and not very objective!

On an auto, launching with a car that won't boost until a significant rpm above the torque converter stall speed makes it feel truly aweful and nasty to drive, while a bigger turbo may be ultimately quicker on a benchmark (such as 0-60) as an everyday driver they are usually too frustrating, heck I've even decided a TD04 is too big for my manual, hence my (oops not done much for a while) Hybrid project.

Simon
 

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01 UK S-Turbo AT
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Simon, I was reading this thinking "great, TD04 for me", but now wonder if the easiest, most practical route is to 'max out' existing hardware including sticking with existing turbo (model/make unknown!!), new air in and out, remap, fuel pump, injectors(?). Presumably a new set of blades in the existing turbo would also improve matters..?

Can anyone tell me why when a turbo lets go you get a big puff of blue smoke out the back (of your Nissan Bluebird)?

cheers
mike
 

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2015 Triumph Tiger XCx 1 Down. 5 Up.
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I guess it depends on how you want to tune it and what engine... the same turbo on a 2.5 will definitely perform differently to a 2.0 and I certainly don't doubt that a TD05 will produce more power than a TD04 simply because it shifts more air.

However, a bigger turbo will spool more slowly than a smaller one for a given volume of air/exhaust gas per second. Since a 2.5 will be displacing more air per revolution than a 2.0 I would expect that the slower spool would be less noticeable and it's possible that a TD05 suits the 2.5 better than a TD04. I don't have any empirical data to back this up though so I'm happy to be corrected.

I'm told that the stock cams and a TD04s peak efficiency coincide very well which makes it a good match for the 2.0.

For me, I'm not after the last 1% of grunt and I'm not bouncing off the redline in every gear. Which is why I'm fitting a TD04 to my 2.0 XT next month.
 

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Don, King of the parts diagram
MY11 WRX STi Sedan 6MT
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Getting back to Deebom's original question...........

TD04 or TD05-That is the question: There aint much difference in the price of second hand ones. So which is it be on a UK 99 s turbo auto?
As has been said before, TD04 is the way to go.

The TD05's, you are talking about (from breakers yards) will have come off an early Impreza and will have a 90degree entry cover on the compressor.
IF you wanted to fit one you would need to factor in cover machining as well.

 
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